HI IVE GOT A T3/T4 ON MY SAFF BEEN ON FOR AGES WORKING GREAT BUT NOW I OVERBOOST TO 25 PSI AT 4000 RPM THEN DROPS TO 20 THEN JUST FLICKERS UP AND DOWN BETWEEN 20 AND 23 PSI UP TO 6000 RPM THEN SETTLES AT 20. THATS AT FULL THROTTLE. IF I HOLD IT AT PART THROTTLE IT WILL HOLD 18 PSI WILL NO JUMPING BOOST AT ALL.
WHEN IM DRIVING IT AND THE BOOST IS JUMPING UP AND DOWN BY 3 PSI I CAN JUST FEEL IT, HAS ANYBODY GOT ANY IDEAS WHAT COULD BE CAUSING THIS AND IF IT WILL DAMAGE MY ENGINE ?
IM RUNNING GREENS, 4X4 INTERCOOLER AND GROUP A FUEL PUMP AND COIL. ANY ADVICE WOULD BE MUCH APPRECIATED.
HAS ANYBODY HAD THIS HAPPEN TO THEMSELVES ?

 

Valve is starting to leak maybe ?, how many miles has the turbo done ?
Is the pivot shaft worn, ie play in out side to side does it feel loose.
tabetha

 

turbo has done about 9000 miles theres play in and out and up and down but no smoke or excessive oil consumption.
the penny fell of and disapeared of the wastegate arm 3 weeks ago so had a new one fitted on is this the valve you mean that could be leaking ?
do you know if this fluctuating boost could damage my engine ? wondered if it could geek the ecu out and maybe run lean ?

 

might be a faulty actuator?